CAIRO – Egypt descended into a chaotic bloodbath – and another political crisis - Wednesday after security forces backed by bulldozers moved into opposition protest camps set up by supporters of ousted president Mohammed Morsi, sparking deadly violence.

Interim Prime Minister Hazem el-Beblawi spoke in a televised address late Wednesday of a "difficult day for Egypt" but said the government had no choice but to order the crackdown to prevent anarchy spreading.

"We found that matters had reached a point that no self-respecting state could accept," he said.

Early Thursday, the country's health ministry announced that at least 327 people were killed and 2,930 others injured. That toll looked certain to rise as unrest spread from Cairo to other parts of the country.

Protesters wrapped the body of one man who had been shot in the chest.

"It is nasty inside, they are destroying our tents. We can't breathe inside and many people are in hospital," volunteer Murad Ahmed told a Reuters correspondent at the Rabaa camp in the Nasr City district of the city.

"We are here, all of us, we are willing to be dead here for the sake of freedom," a professor of ophthalmology at the scene told NBC News. "They are shooting us with guns...and killing people here and we have nothing in our hands, we have nothing in our hands."

Among those killed were Asmaa Beltagy - the 17-year-old daughter of Mohammed Beltagy, one of the Muslim Brotherhood's top leaders - and at least two international journalists.

At one stage, a woman was seen trying to stop a bulldozer from causing further injury to a wounded youth.

At a hospital morgue, a Reuters reporter counted 29 bodies, including that of a 12-year-old boy. Most had died of gunshot wounds to the head.

Egypt’s interior ministry said only tear gas had been used to clear the sit camps, but a Reuters reporter said he saw about 20 protesters who had been shot in the legs by soldiers.

Pro-Morsi protesters were seen throwing stones and Molotov cocktails at troops, Reuters reported.

The violent scenes prompted an angry backlash across Egypt, including attacks on churches and the killing of an air force colonel in a highway ambush.

Egyptian security forces move in to clear one of the two sit-in sites of supporters of ousted president Morsi, Wednesday.Mostafa Darwish / EPA

A police station was stormed in the Giza district of Cairo - near the location of the second camp at Nahda – and all four officers inside were killed.

At one stage, armed protesters were inside Cairo Zoo, firing at police, state television reported.

The U.S. Embassy was closed, the country’s stock exchange suspended and train services halted,

United Nations Secretary General Ban Ki-moon condemned the violence used by Egypt’s security forces.

“While the UN is still gathering precise information about today's events, it appears that hundreds of people were killed or wounded in clashes between security forces and demonstrators,” he said in a statement.

Turkey’s prime minister called on the United Nations Security Council to help, describing Wednesday's events as a “massacre.”

"The international community, especially the U.N. Security Council and Arab League, must act immediately to stop this massacre," Tayyip Erdogan's office said in a statement.

The sit-in camps were formed in protest at the military-backed July 3 ouster of democratically elected Morsi.

More than 300 people have already died in political violence since the army deposed Morsi exactly 12 months into his four-year term as president.